What the heck, we're all just guessing here, right? I'm going to guess a heavy metal issue. Maybe there's a problem with some of your LR, or maybe somebody played "wishing well" with a few pennies you haven't noticed... In the case of any metal, the process of leeching takes a while, so I'd do a couple of massive water changes ~50% or so, and then introduce some snails. If they live for a while, then die in a week or two, you'll be replacing a lot of your LR...
Just guessing. Free advice is worth the price you pay.
Matthew
|